High flow cats vs other exhaust input

[JRSViperRT]

I am wanting to add some more aggressive sound to my 94 RT 10 without making it impossible to drive. I have read a lot of set ups and would love input from those who have done some of these.

I am all stock now.

I prob will not do headers at this time unless there is a great deal going on. I do want to lessen the sill temps while making it aggressive yet drivable.

I had a challenger SRT with American thunder flow masters and loved the sound but the drone at Highway was annoying over time.

Thanks for your thoughts!

 

[maverickagm]

I'm interested in the same information. I have a '93 with stock exhaust. I'm open to installing headers as long as the under-hood temps don't get out of hand. The only oppinion I've come across is this:

New exhaust on my '94 Viper is epic! You've got to hear the muscle car rumble. Test drive time!

The stock exhaust wasn't the right sound for the CAR WIZARD's ‍♂️ 1994 Dodge Viper. After a bit of trouble sorting the new exhaust the end result is absolu...

www.youtube.com

 

[JRSViperRT]

I'm interested in the same information. I have a '93 with stock exhaust. I'm open to installing headers as long as the under-hood temps don't get out of hand. The only oppinion I've come across is this:

New exhaust on my '94 Viper is epic! You've got to hear the muscle car rumble. Test drive time!

The stock exhaust wasn't the right sound for the CAR WIZARD's ‍♂️ 1994 Dodge Viper. After a bit of trouble sorting the new exhaust the end result is absolu...

www.youtube.com

I watched this same video as well. He provides some good information

 

[Bill W]

I have hi-flow cats on my '02 Viper. No drone and, like a fine wine, they get better (a little louder) over time. For me, it's the perfect subtle sound of power. Not too loud and definitely not stock, which was way too mellow for a Viper.

 

[Old School]

I would suggest just removing the cats, if you can get by with it in your state, and leave the rest alone. See how it sounds, exhaust sound is subjective. It will be significantly louder with much lower sill temp.

Some like to use high flow cats as an expensive muffler, but that just adds heat.

 

[TEALLIFE]

High Flow cats will increase the sound significantly. There's no reason not to run them these days. Especially with the stock ones breaking down and potentially catching fire.

 

[GTS Dean]

Sidepiped RT's will get stupid loud very quickly if you gut them too aggressively. HF cats are fine, but I would definitely recommend some quality mufflers. I rode as a Viper Days instructor with a guy in a 95 RT/10 with gutted sidepipes way back in the day. The volume and resonance was so bad I pointed him back in the pits on lap 3 and walked away.

I have TNT 5:1 headers, 3" HF cats and Moroso Spiral Flow mufflers in the sills, then a 2.5" X-pipe out the rear. There is Zero resonance in the cabin and is satisfyingly loud enough when romping.

 

[JRSViperRT]

Thank you for the recommendations and experience. I definitely want to keep the side exhaust and want that deep growl when getting on it without losing my hearing

 

[white out]

I ran ARH headers on my GEN2 with stock mufflers and it sounded nice, had good power, dropped a bunch of weight weight and was very reasonable in the sound department. On a GEN1 I think that would be a good setup because it would make more power than post-header exhaust changes and not be annoyingly loud for side pipes.

After the OEM exhaust I swapped to a 3" exhaust with bullet mufflers and it became ridiculously loud.

 

[Peter Kater]

Hi there!
As suggested here already, if you can pass emissions in your state, just get rid of the cats.
If not, then just slap high flow cats on. You'll get a way better sound (less restrictive than stock) and will still be able to pass emissions.
For the temperature.. Hmm.. High flow cats will help decrease the overall temp in the sills, but if you really really want to like "save" your sills paint from deteriorating, then (I'm sorry) but you'll need to go the full game like this:
1. Install an air intake grill in the front side of the sill (cutting required). I think JonB sells those air intake grills..
These grills apply right on the side of the sills that is facing the front tire.
2. Remove the sills from the car and re-insulate them with proper modern insulation material (self adhesive face is available).

In that way, you'll get better sound and lower sills temps.

Enjoy your ride Sir!

 

[Tom and Vipers]

FYI - saw this thread: I have a set of OE cats from 96 GTS that were removed when the new exhaust was installed. I bot the car with 60k on it in 2001. It was taken to TNT in 1999 for heads/cam for sure, not sure if they did headers/exhaust. Headers most likely and who wouldn't go for exhaust at that time? So guessing 30-40k on the cats. The story I heard about them is they are a series stack of 2 common cores that Chrysler used on other cars/trucks. I'm selling car, may go with car, may be for sale? haven't thought about this until read this thread...

 

[JonB]

One of our most successful, highest-rated, happy-owners, is High-Flow-Cats options. YEAR MATTERS!

2.5" or 3.0" or graduated 2.5+3.0.
Catalyst Substrate choices.

As noted, G1-3-4-5 sidepipers require a bit more planning to get the Goldilocks just-right sound that YOU want.

Cooler sidesills, cooler footwell, and even cooler cockpits [G3 crossover delete] can be a bonus.

Remember: Cats Dont Commit Suicide. They foul with age and neglect of maintenance of fuel-ignition components: Coils, Wires, Plugs, etc

[email protected]

 

[JRSViperRT]

If I do the high flow cats first do you all recommend insulating better inside the sills with some heat shield material?

 

[Old School]

If I do the high flow cats first do you all recommend insulating better inside the sills with some heat shield material?

High flow cats basically just don't function as well as the stock ones. When cats are working, they generate heat. Since high flows don't convert as much gas, they don't generate as much heat, so maybe you can get by with the factory insulation......

 

[Bill W]

You could look into Heatshield Armor. That's what I did on my Gen 2 along with hi-flow cats. The sound is perfect for me and the heat issue has been abated. The cats were not wrapped. Mechanic said it's best not to.

 

[MoparMap]

If I do the high flow cats first do you all recommend insulating better inside the sills with some heat shield material?

I saw in a different thread in the past where someone had an earlier gen that had the gen 3/4 side sill insulation retro fitted. It seems to be reasonably good stuff and it works by mounting to the sill itself instead of the exhaust, so I think it's better for pipes in that it tends to do better about letting air flow around them and not holding moisture against them.